This article presents the analysis of feedback to grammatical mistakes in two English as a Foreign Language (EFL) classrooms and how learners view this kind of correction. The data are drawn from transcripts of audio-recordings of ten classes of two pre-intermediate groups, totaling 7.5 hours of observation in each group. The two groups were taught by the same teacher, and a questionnaire was given to the learners in order to investigate their feelings about the teacher's feedback procedure. The analysis was carried out through a sociocultural perspective and reveals that (1) explicit correction is the most frequent type of feedback to grammar mistakes, and (2) learners appreciate and consider the teacher's correction highly important for the development of their language skills.